code: def test_gco_params_setter():
      new_gco = gco.GCO()
  
      try:
          new_gco.CR = "a"
      except:
          new_gco.CR = 0.75
  
      try:
          new_gco.CR = -1
      except:
          new_gco.CR = 0.75
  
      assert new_gco.CR == 0.75
  
      try:
          new_gco.F = "b"
      except:
          new_gco.F = 1.5
  
      try:
          new_gco.F = -1
      except:
          new_gco.F = 1.5
  
      assert new_gco.F == 1.5
  
file_path: opytimizer/tests/opytimizer/optimizers/population/test_gco.py
imports: import numpy
  from opytimizer.optimizers.population import gco
  from opytimizer.spaces import search
label_desc: Use image node_id 2 for calling a global function with example usage: test_gco_params_setter() without return types